1. Field of the Invention
The present invention relates to a recording apparatus having recording means for outputting input information such as character, image and so on onto the recording medium, a recording system as an information processing system, such as a copying machine, a facsimile machine, a printer, a word processor, or a personal computer, comprising said recording apparatus as output means, and a drive switching method for use with said recording apparatus.
2. Related Background Art
The recording apparatus performs the recording by driving recording means having a plurality of recording elements for outputting the input information such as character, image and so on onto the recording medium (such as a paper, a cloth, a plastic sheet, etc.) under control of control means. The recording apparatuses can be classified into an ink jet system, a wire dot system, a thermal system, a thermal transfer system, and a laser beam system, depending on the recording system of recording means to be used. Among these recording apparatuses, in a serial type recording apparatus which takes a recording method of effecting recording by causing recording means to scan in a direction crosswise to the conveying direction (sub-scan direction) of recording medium, the image recording over the entire area of recording medium is accomplished in such a way that after setting the recording medium at a predetermined recording position, the image recording (main scanning) operation by recording means (recording head) mounted on a carriage moving along the recording medium is carried out by repeatedly performing paper feeding (sub-scanning) by a predetermined amount after one line of recording, and then recording (main scanning) of image at the next line.
Typically, in the serial type recording apparatus, a step motor is mostly used as a carriage drive motor for driving a carriage useful for the main scanning (scanning for recording) of a recording head. Also, as a drive motor for feeding the recording medium in a direction perpendicular to a movement direction of carriage, a step motor is also mostly used. Further, an apparatus has been developed in which only one drive source is used to perform plural operations to reduce the motors for the purposes of lower costs and saved space.
One such serial type recording apparatus is known in which the drive transmission path for paper feed driving is switched by the use of the movement of carriage outside the recording area, as described in Japanese Laid-Open Patent Application No. 59-145175, for example. Also, one way of switching such drive path is known in which the disconnecting/switching of drive transmission path is effected by the use of a missing teeth portion of a gear in a drive transmission system, as described in Japanese Laid-Open Patent Application No. 4-288264, for example.
By applying such technologies, an ink jet recording apparatus was manufactured having a drive transmission path for transmitting the drive which is switched by selecting a paper feeding and a recovery pump by means of a gear with an untoothed portion by the use of the movement of carriage outside the recording area, but there was observed a phenomenon that the unnatural sound occurred from near the gear with the untoothed portion. Analyzing its cause, it has been found that the sound was produced by the contact between the untoothed end portion of the gear with untoothed portion and the tooth of a gear opposite the gear with untoothed portion, without regard to the drive transmission.
Also, because such abnormal contact condition between gears caused a defect in the gear, there was a risk that normal drive transmission might be hampered.